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Background The prognostic implications of non-sustained ventricular tachycardia (NSVT) and their significance as therapeutic targets in patients without prior sustained ventricular arrhythmias remain undetermined. The aim of this study was to investigate the prognostic significance of asymptomatic NSVT in patients who had primary prevention implantable cardioverter-defibrillator (ICD) implantation due to ischemic or non-ischemic cardiomyopathy (ICM, NICM). Methods We enrolled 157 consecutive primary prevention ICD patients without previous appropriate ICD therapy (AIT). Patients were allocated to two groups depending on the presence or absence of NSVT in a 6-month period prior to enrollment. The incidence of AIT and unplanned hospitalization due to decompensated heart failure (HF) were assessed during follow-up. Results In 51 patients (32%), precedent NSVT was documented. During a median follow-up of 1011 days, AIT occurred in 36 patients (23%) and unplanned HF hospitalization was observed in 32 patients (20%). In precedent NSVT patients, the incidence of AIT and unplanned HF hospitalization was significantly higher as compared to patients without precedent NSVT (AIT: 29/51 [57%] vs. 7/106 [7%], P P = 0.043, log-rank). Cox-regression demonstrated that precedent NSVT independently predicted AIT (P P P = 0.020), but predicted HF hospitalization only in patients with ICM (P = 0.0030). Conclusions Precedent non-sustained VT in patients with primary prevention ICDs is associated with subsequent appropriate ICD therapies, and is an independent predictor of unplanned heart failure hospitalizations in patients with ischemic cardiomyopathy.

Introduction The single-chamber implantable cardioverter-defibrillator (ICD) can be associated with more frequent inappropriate therapies compared with dual-chamber ICDs, when they are accompanied by a simpler implantation procedure. The aim of this study was to investigate whether the use of a single-lead ICD system with atrial-sensing electrodes results in a reduction of inappropriate ICD therapy. Methods and results The study population consisted of 212 consecutive patients, who underwent primary prophylactic single-lead ICD implantation at our institute. A ventricular lead with atrial-sensing electrodes was implanted in 77 patients (36%; Group-VDD) and a ventricular lead without atrial-sensing electrodes was implanted in 135 patients (64%; Group-VVI). Procedural and follow-up data were collected in a prospective registry. A higher prevalence of atrial fibrillation was present in Group-VDD. There were no other significant differences in patient baseline characteristics (age, sex, and other comorbidities) or follow-up period between the two groups. The operative parameters including fluoroscopic burden showed no significant differences between Group-VDD and Group-VVI. During a mean follow-up period of 697 ± 392 days, 26 patients (12%) experienced appropriate ICD therapies and 13 patients (6%) suffered inappropriate ICD therapies. The incidence of inappropriate ICD therapies in Group-VDD was significantly lower as compared to that of Group-VVI (1/77 [1%] vs 12/135 [9%]; log-rank, P = 0.028). The incidence of appropriate ICD therapies and the occurrence of device-related complications showed no significant difference between the two groups. Conclusion Single-lead ICD with atrial-sensing electrodes shows a lower incidence of inappropriate ICD therapy compared with the absence of atrial-sensing electrodes, without additional operative burden or increased complications.

Background: The severity of symptoms during atrial fibrillation (AF) may be influenced by heart rate and blood pressure variation, due to irregular beats and the related adaptations in baroreflex sensitivity. This study investigated whether heart rate turbulence (HRT) as a reflection of baroreflex sensitivity is related to symptom severity during AF. Method: Ninety-seven patients (pts) who underwent electrophysiological study were enrolled. Consecutive 56 pts had paroxysmal AF (21 with milder symptoms [EHRA I or II; Group-M], 35 with severe symptoms [EHRA III or IV; Group-S]), and 41 age-matched controls without AF were included. After delivering a single ventricular extrastimulus during sinus rhythm and repeating the process 10 times, the quantification of HRT was performed by measuring turbulence onset (TO: heart rate acceleration) and turbulence slope (TS: rate of heart rate deceleration). Results: Group-M pts showed significantly diminished TO as compared to controls and Group-S pts (P = 0.012). There was no significant difference of the TS between the 3 groups. Given that a TO ≥ 0% or TS ≤ 2.5 ms/RR was considered abnormal, Group-M pts showed significantly higher incidences of abnormal HRT as compared to controls and Group-S pts (71% vs 40% vs 21%, respectively, P = 0.0012). Regression analysis demonstrated an independent and significant association between a diminished TO and milder AF symptoms (P

Idiopathic ventricular tachycardia: Frequent monomorphic premature ventricular contractions or non-sustained ventricular tachycardia without underlying structural heart disease is not a rare condition and may cause significant symptoms. A subgroup of patients develops IVT-associated cardiomyopathy. Current ESC guidelines recommend primary catheter ablation in symptomatic patients with right ventricular outflow tract IVT. Catheter ablation is also recommended in symptomatic patients with a left ventricular outflow tract (or other rare) origin, if antiarrhythmic drugs are ineffective or not desired.Ventricular tachycardia associated with structural heart disease: Scar-associated ventricular arrhythmias may cause sudden cardiac death in a variety of heart diseases. While ICD implantation has been shown to reduce mortality, repetitive ICD shocks impact on survival and quality of life. In a recent meta-analysis, both amiodarone and catheter ablation reduce the incidence of recurrent ICD shocks. Discontinuation of amiodarone due to side effects is common. Current ESC guidelines recommend both strategies (class 1 indication). Catheter ablation is also recommended in drug-resistant VT or electrical storm. A totally subcutaneous ICD is a novel option in patients not requiring pacing.

Atrial fibrillation (AF) is associated with thromboembolic events. Currently, the CHA2DS2-VASc score is recommended for thromboembolic risk stratification in non-valvular AF patients. However, recent data suggested a potential role of atrial remodelling on thromboembolism. This study aimed to assess the association between left atrial low-voltage area (LVA) and history of clinical manifest as well as subclinical silent cerebral ischaemia (SCI) in AF patients.Two-hundred patients [64 ± 10.5 years, 75 women (37.5%)] with symptomatic paroxysmal (n = 88, 44%) or persistent AF undergoing pulmonary vein isolation (PVI) were prospectively enrolled. Left atrial LVA (bipolar voltage 0.5mV) was evaluated by intra-procedural mapping (300 points per patient) during sinus rhythm. Cerebral delayed-enhancement magnetic resonance imaging was performed after PVI for detection of pre-existing procedural-independent SCI. Over all, 17 patients (8.5%) had previous history of stroke. Pre-existing SCIs were detected in 135 patients (67.5%). Patients with previous stroke (4.0 ± 1.5 vs. 2.1 ± 1.3, P 0.0001) and pre-existing SCI (2.7 ± 1.3 vs. 1.5 ± 1.4, P 0.0001) had a significantly higher CHA2DS2-VASc score. LVA was significantly larger in patients with previous stroke (12.5 ± 8.5% vs. 3.4 ± 5.4%, P 0.0001) as well as pre-existing SCI (5.8 ± 6.9% vs. 0.8 ± 1.7%, P 0.0001). Multivariate regression analysis revealed that LVA was independently associated with the presence of SCI [hazard ratio (HR) per 1% LVA 1.13 (1.06-1.22), P = 0.0003] and history of stroke [HR per 1% LVA 1.36 (1.19-1.60), P 0.0001] after adjustment of CHA2DS2-VASc score.Left atrial LVA is associated with history of stroke and SCI in patients with non-valvular AF and might improve thromboembolic risk stratification after confirmation of its predictive value in future studies.

The ideal energy dosing remains unclear in second-generation cryoballoon (CB) pulmonary vein isolation (PVI). We aimed to investigate the effect of an individualized dosing strategy based on time to PVI (TTI).The purpose of this study was to prospectively investigate the safety and efficacy of individualized PVI using the second-generation CB guided by real-time pulmonary vein recordings.Two groups were prospectively randomized: ICE-T group: if TTI75 seconds, then no bonus freeze; and control group: acute PVI followed by 1 empiric bonus freeze. Freeze duration was set to 240 seconds. The primary end point was single procedure sinus rhythm after 12 months (blanking period 3 months). Secondary end points included procedural data, complications, and biomarker release.In total, 100 patients with paroxysmal atrial fibrillation were randomized. The primary end point was not different (88% vs 82%). Procedure and fluoroscopy times were significantly shorter in the ICE-T group (70 ± 20 minutes vs 89 ± 21 minutes; P.001 and 10.6 ± 3.9 minutes vs 12.7 ± 5.5 minutes; P = .03). More complications occurred in the control group (n = 9 vs n = 3) (persistent phrenic nerve injury: n = 1 vs n = 0; transient phrenic nerve injury: n = 5 vs n = 2; esophageal lesions: n = 3 vs n = 1). Postablation troponin T levels were not different (ICE-T group vs control group: 1035 ± 402 ng/L vs 1219 ± 509 ng/L; P = .099), whereas a significantly lower lactic acid dehydrogenase release was observed in the ICE-T group (259 ± 47 U/L vs 282 ± 57 U/L; P = .038). Multivariate analysis identified a mean TTI of43 seconds as the only independent predictor of recurrent atrial tachyarrhythmia.The individualized CB PVI strategy allows faster atrial fibrillation ablation without affecting the favorable clinical outcome. A short TTI appears to predict freedom from recurrent atrial tachyarrhythmia.

Background: The FIRE AND ICE trial assessed efficacy and safety of pulmonary vein (PV) isolation using cryoballoon versus radiofrequency current (RFC) ablation in patients with drug refractory, symptomatic, paroxysmal atrial fibrillation (AF). The purpose of the current study was to assess index lesion durability as well as reablation strategy and outcomes in trial patients undergoing a reablation procedure. Methods: Patients with reablation procedures during FIRE AND ICE were retrospectively consented and enrolled at 13 trial centers. The first reablation for each patient was included in the analysis. Documented arrhythmias before reablation, number and location of reconnected PVs, lesions created during reablations, procedural characteristics, and acute as well as long-term outcomes were assessed. Results: Eighty-nine (36 cryoballoon and 53 RFC) patients were included in this study. Paroxysmal atrial fibrillation was the predominant recurrent arrhythmia (69%) before reablation. Reablations occurred at a median of 173 and 182 days ( P =0.54) in the cryoballoon and RFC cohorts, respectively. The number of reconnected PVs was significantly higher in the RFC than the cryoballoon group (2.1±1.4 versus 1.4±1.1; P =0.010), which was driven by significantly more reconnected left superior PVs and markedly more reconnected right superior PVs. The number of (predominantly RFC) lesions applied during reablation was significantly greater in patients originally treated with RFC (3.3±1.3 versus 2.5±1.5; P =0.015) with no difference in overall acute success ( P =0.70). After reablation, no differences in procedure-related rehospitalization or antiarrhythmic drug utilization were observed between cohorts. Conclusions: At reablation, patients originally treated with the cryoballoon had significantly fewer reconnected PVs, which may reflect RFC catheter instability in certain left atrial regions, and thus required fewer lesions for reablation success. Repeat ablations were predominantly performed with RFC and resulted in similar acute success, duration of hospitalization, and antiarrhythmic drug prescription between the study cohorts. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT03314753.

Sudden cardiac death (SCD) is frequent in patients with heart failure due to dilated cardiomyopathy (DCM). Implantable cardioverter/defibrillator (ICD) device therapy is currently used for primary prevention. However, publication of the DANISH trial has recently given reason for doubt, showing no significant improvement in all-cause mortality in comparison to contemporary medical therapy. We performed a meta-analysis of all randomized controlled trials comparing ICD therapy to medical therapy (MT) for primary prevention in DCM. The primary outcome was all-cause mortality; secondary analyses were performed on sudden cardiac death, cardiovascular death and non-cardiac death. Five trials including a total of 2992 patients were included in the pooled analysis. Compared to contemporary medical treatment there was a significant mortality reduction with ICD device therapy [odds ratio (OR) 0.77, 95% confidence interval (CI) 0.64–0.93; p = 0.006]. SCD was decreased significantly (OR 0.43, CI 0.27–0.69; p = 0.0004), while cardiovascular death and non-cardiac death showed no differences. Sensitivity analyses showed no influence of amiodarone therapy on overall results. Analysis of MT details revealed the DANISH population to adhere the most to current guideline recommendations. In addition, it was the only study including a substantial amount of CRT devices (58%). Our meta-analysis of all available randomized evidence shows a survival benefit of ICD therapy for primary prevention in DCM. DANISH results suggest an attenuation of this ICD advantage when compared to contemporary medical and cardiac resynchronization therapy. Until larger trials have confirmed this finding, ICD therapy should remain the recommendation for primary prevention of SCD in DCM.

Objectives The aim of this study was to identify predictors of cardiac tamponade (CT) during atrial fibrillation (AF) ablation using different technologies and strategies. Background The major cause of death during catheter ablation of AF is related to CT. The risk for CT may be linked to different procedural steps (transseptal puncture, catheter manipulation during left atrial and pulmonary vein mapping and ablation). Methods All AF ablation procedures undertaken from May 2010 to July 2015 at a single center were included. Two ablation groups were defined: group A, radiofrequency current, and group B, balloon. Group A was divided into groups A1 (pulmonary vein isolation [PVI] only) and A2 (PVI plus additional ablation). In group A, 2 transseptal punctures were performed, followed by wide-area circumferential point-by-point PVI (group A1) within a 3-dimensional left atrial map and complex fractionated atrial electrograms and/or linear lesions (group A2). In group B, 1 transseptal puncture by balloon-based PVI (cryoballoon, laser balloon). All episodes of CT were analyzed. Results In total, 3,000 AF ablation procedures were performed, 2,125 in group A (group A1, n = 1,559; group A2, n = 566) and 875 in group B (cryoballoon, n = 589; laser balloon, n = 286). The rate of CT was 1.1% (32 of 3,000) and was significantly lower in group B than in group A: 0.1% (1 of 875) versus 1.5% (31 of 2,125) (p = 0.001). The reduced CT risk remained if PVI only (group B vs. group A1) was compared: 0.8% (13 of 1,559) versus 0.1% (1 of 875) (p = 0.024). The greatest CT risk was seen in group A2: 3.2% (18 of 566). Radiofrequency current ablation beyond PVI was a predictor of CT. Conclusions The risk for CT in patients undergoing AF ablation at a single high-volume center was decreased with the use of balloon catheters. Extensive radiofrequency current ablation beyond PVI leads to an increased perforation risk.

Background: Data on predictors of long-term clinical outcomes after catheter ablation of atrial fibrillation (AF) are limited. We sought to assess the association of baseline covariates with clinical outcomes in the 750 patients with drug-refractory paroxysmal AF enrolled in FIRE AND ICE. Methods: In a 2-part analysis, univariate and multivariable Cox regression models were first used to identify baseline patient characteristics predictive of catheter ablation efficacy determined by the clinical end points of (1) atrial arrhythmia recurrence (primary efficacy failure), (2) cardiovascular rehospitalization, and (3) repeat ablation. Propensity score stratification methods were then used to account for differences in baseline characteristics between sexes. RESULTS: Female sex (hazard ratio [HR], 1.37; 95% confidence interval [CI], 1.08–1.73; P =0.010) and prior direct current cardioversion (HR, 1.40; 95% CI, 1.07–1.82; P =0.013) were independently associated with atrial arrhythmia recurrence. Female sex (HR, 1.36; 95% CI, 1.02–1.80; P =0.035) and hypertension (HR, 1.48; 95% CI, 1.09–2.00; P =0.013) independently predicted cardiovascular rehospitalization. A longer history of AF (HR, 1.03; 95% CI, 1.00–1.06; P =0.039) increased the rate of repeat ablation. Women continued to have higher rates of primary efficacy failure and cardiovascular rehospitalization after propensity score adjustment, with adjusted HRs of 1.51 (95% CI, 1.16–2.18; P P Conclusions: After catheter ablation of paroxysmal AF, female sex was associated with an almost 40% increase in the risks of primary efficacy failure and cardiovascular rehospitalization. Primary efficacy failure was also adversely impacted by a history of direct current cardioversion, whereas hypertension had a negative impact on cardiovascular rehospitalization. History of AF was the only predictor of repeat ablation. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01490814.

Aims Several studies demonstrated an inverse relationship between cardioverter-defibrillator implantation volume and complication rates, suggesting better outcomes for higher volume centres. However, the association of institutional procedural volume with patient outcomes for permanent pacemaker (PPM) implantation remains less known, especially in decentralized implantation systems. Methods and results We performed retrospective examination of data on patients undergoing PPM from the German obligatory quality assurance programme (2007–12) to evaluate the relationship of hospital PPM volume (categorized into quintiles of their mean annual volume) with risk-adjusted in-hospital surgical complications (composite of pneumothorax, haemothorax, pericardial effusion, or pocket haematoma, all requiring intervention, or device infection) and pacemaker lead dislocation. Overall 430 416 PPM implantations were documented in 1226 hospitals. Systems included dual (72.8%) and single (25.8%) chamber PPM and cardiac resynchronization therapy (CRT) devices (1.1%). Complications included surgical (0.92%), and ventricular (0.99%), and atrial (1.22%) lead dislocation. Despite an increase in relatively complex procedures (dual chamber, CRT), there was a significant decrease in the procedural and fluoroscopy times and complications from lowest to highest implantation volume quintiles ( P for trend

Background An increased incidence of esophageal lesions (EL) after pulmonary vein isolation (PVI) using the second-generation cryoballoon (CB2) has been described. We hypothesized that luminal esophageal temperature (LET)–guided PVI reduces the incidence of EL. Objective The aim of this study was to investigate the incidence of EL after LET-guided PVI using the CB2. Methods Ninety-four consecutive patients underwent CB2-PVI for paroxysmal or persistent atrial fibrillation. Target freezing time was 2 × 240 seconds. LET was continuously measured by a probe with 3 thermocouples. Early freezing interruption was performed when LET reached a prespecified cutoff temperature. A group of 32 patients who underwent CB2-PVI with observational LET measurement served as the control group. Postprocedural esophagoscopy was performed in all patients. Results Compared with observational LET measurement, a strategy of LET-guided CB-PVI significantly reduced the incidence of EL from 18.8% to 3.2% ( P = .008). A progressive decline in the incidence of EL was observed with an increasing LET cutoff: 7.1% (2/28 patients, 12°C cutoff) and 1.5% (1/66 patients, 15°C cutoff, P = .005 vs control). Despite early freezing interruption at a single pulmonary vein in 27% (25/94) of patients, complete PVI was achieved in all patients using the 28 mm balloon. Repeat esophagoscopy confirmed healing of EL after 1 week. After a mean of 268 ± 119 days, 87% (76/87) of patients were free of recurrent atrial fibrillation or atrial tachycardia following a 90-days blanking period. Conclusion LET-guided CB2-PVI significantly reduced the incidence of thermal EL. Interrupting cryoablation at 15 ° C LET was associated with the lowest incidence of esophageal injury.

Aims The second-generation cryoballoon (CB2) with increased surface cooling has recently become available. The aim was to investigate the incidence and characteristics of phrenic nerve palsy (PNP) during pulmonary vein isolation (PVI) using the CB2 as compared with the first-generation balloon (CB1). Methods and results A total of 360 consecutive patients with atrial fibrillation underwent PVI with the CB1 (106 patients) or the CB2 (254 patients). Right PN function was monitored by continuous stimulation and palpation during septal PV ablation. Persistent PNP (present at discharge) occurred in 2.8 and 1.9% ( P = 0.63) of patients, transient PNP (full recovery before discharge) in 5.9 and 3.8% ( P = 0.41) of patients in the CB2 and CB1 group, respectively. Phrenic nerve palsy during ablation at the right inferior PV was observed in 0% (CB1) and 4.3% (CB2, P = 0.03) of patients. Using the CB2, a trend of reduced incidence of persistent PNP over quartiles of consecutive patients was observed [4.8% (Q1) vs. 0% (Q4); P = 0.077]. At the culprit PV, PNP occurred after 3.5 ± 2.1 (CB1) and 1.1 ± 0.4 applications (CB2; P = 0.036). Complete recovery of PN function occurred after 29 ± 11 (CB1) and 259 ± 137 days (CB2; P = 0.004). Conclusions The rate of transient/persistent PNP associated with the use of the CB2 was 5.9 and 2.8%, respectively. Time to restitution of PN function was longer using the CB2.

Background Subclinical atrial fibrillation is one possible cause of embolic stroke of undetermined source ( ESUS ). It remains to be elucidated if a specific infarction site has a predictive value for detecting subclinical atrial fibrillation. We aimed to investigate the predictive value of infarction site in patients with ESUS for the detection of atrial tachyarrhythmia ( AT ) using an insertable cardiac monitor. Methods and Results Consecutive 146 patients (84 men; aged 62±12 years) underwent insertable cardiac monitor implantation after diagnosis of ESUS . The detection of AT >30 seconds was evaluated. The ESUS infarction sites were categorized into internal carotid artery and vertebral artery ( VA ) territories, with ophthalmic artery, anterior cerebral artery, and middle cerebral artery as internal carotid artery subterritories, and posterior cerebral artery and other vertebrobasilar arteries as VA subterritories. During a median follow‐up of 387 days, AT was detected in 33 patients (23%). Subclinical AT detection was significantly more frequent after VA territorial infarction opposed to internal carotid artery infarction (20/57 [35%] versus 13/89 [15%]; P =0.0039). Kaplan‐Meier analysis demonstrated a significantly higher AT detection rate after VA infarction (log‐rank, P =0.0076). Regression analysis revealed that VA territorial infarction, and particularly posterior cerebral artery area infarction, was an independent predictor of AT detection. Conclusions Patients with ESUS in the posterior cerebral artery territory had a higher rate of subclinical AT detection than those with other infarct localizations. Our data suggest that the possible usefulness of ESUS site to identify candidates for direct oral anticoagulation should be confirmed in future research.

Rationale and Design of Fire and IceBackground Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia imposing substantial morbidity and mortality. Catheter-based pulmonary vein isolation (PVI) using radiofrequency current (RFC) has become a standard treatment for drug-resistant and symptomatic paroxysmal AF (PAF). In recent years, the cryoballoon-based technique is increasingly used as a promising alternative with a short learning curve. Methods The FIRE AND ICE trial is a prospective, randomized, controlled, open, blinded outcome assessment, noninferiority trial comparing cryoballoon-, and RFC-based PVI. Patients with drug-resistant PAF will be randomized in a 1:1 matrix in multiple European centers. The primary hypothesis is that cryoballoon ablation is not inferior to RFC ablation using 3-dimensional mapping with respect to clinical efficacy. The primary endpoint is defined as the time to first documented clinical failure, including: (1) recurrence of AF; (2) atrial flutter or atrial tachycardia; (3) prescription of class I or III antiarrhythmic drugs; or (4) re-ablation, whichever comes first, following a blanking period of 3 months after the index ablation procedure. The primary safety endpoint is a composite of death, stroke/transient ischemic attack, cardiac arrhythmias (apart from AF recurrence) causally related to the therapeutic intervention, and procedure-related serious adverse events. Conclusion The FIRE AND ICE trial compares 2 different technologies to perform catheter ablation of PAF with respect to efficacy and safety. It aims at providing objective data to guide selection and usage of ablation catheters in the treatment of AF.

Learning Curve of Laser Balloon PVI Introduction Novel ablation devices for pulmonary vein isolation (PVI) need a careful evaluation of its efficacy and safety beyond clinical studies in a real world situation. The endoscopic ablation system (EAS) was recently approved for PVI in Europe. We sought to determine the safety, efficacy, and learning curve effects of EAS-PVI in a large volume single center. Methods and Results Between June 2010 and March 2013, all EAS guided PVI procedures were analyzed and 150 consecutive patients were divided in tertiles (T). Clinical follow-up of 12 months assessed freedom from atrial fibrillation (AF) using 72 hour-Holter ECG recordings. In total, 497 of 583 PVs (85%) were isolated by visual guidance only. In T 2 and T 3, visually guided PVI rates increased from 73% to 91% (P < 0.001). After gap mapping, 96% and 99% of all PVs were isolated in T 1–3, respectively (P = 0.018). Total procedure and fluoroscopy time significantly declined over time. All major periprocedural complications occurred in the first T. In 3 patients (2 in 1st and 1 in 2nd T), phrenic nerve palsy was observed (2%). At 12-months follow-up, 103 of 133 patients (77%) remained in stable sinus rhythm without significant differences between Ts. Conclusion With EAS even first time users may achieve acute PVI in a high number of patients with favorable clinical outcomes after 1 year. Yet, acute procedural efficacy and safety are further improved after passing a learning curve of 50 patients.

Improved Efficacy of Second-Generation CryoballoonBackground The second-generation cryoballoon (CB2) has recently been introduced featuring improved surface cooling. Increased procedural efficacy of pulmonary vein isolation (PVI) when compared to the first-generation balloon (CB1) has been reported. The aim of the study was to investigate the clinical outcome of cryoballoon PVI after 1 year using the CB2 as compared to the CB1. Methods and Results A total of 105 consecutive patients with paroxysmal atrial fibrillation (AF) were studied. Cryoballoon PVI (28 mm) was performed in 50 patients using the CB1, and in 55 patients using the CB2. Patients were scheduled for 72-hour Holter ECG recording at 3, 6, 9, and 12 months and every 6 months thereafter. The study endpoint was defined as recurrent AF or atrial tachycardia >30 seconds documented after a blanking period of 90 days after the procedure. Complete PVI was achieved in 49/50 (98%) and 55/55 (100%) patients in the CB1 and CB2 group, respectively. After a mean follow-up of 416 ± 75 days, 21 (CB1 group) and 10 (CB2 group) patients reached the study endpoint. Kaplan–Meier estimates of arrhythmia-free survival after a single procedure without AAD therapy after 1 year were 63.9% versus 83.6% (P = 0.008) in the CB1 and CB2 group, respectively. Persistent phrenic nerve palsy with delayed healing occurred in 2 (CB1 group) and 3 (CB2 group) patients. Conclusion Clinical outcome of PVI using the CB2 was significantly improved when compared to the CB1.

Aims Recently, a novel second-generation (G2) cryoballoon (CB) was introduced. Comparative analysis of lesion formation in terms of myocardial biomarker release [first-generation CB (G1) vs. G2] has not been studied. To compare myocardial biomarker release using the 28 mm G1 vs. G2 CB. Methods and results In patients (patients) treated with the simplified single big CB (SBCB) strategy for pulmonary vein isolation (PVI), myocardial biomarkers [troponin T (TnT), creatine kinase, lactic dehydrogenase (LDH)] were measured at 12, 24, and 48 h after PVI. Two groups were defined: Group 1 (G1; freezing time: 300 s), Group 2 (G2; freezing time: 240 s). Mean biomarker peak values were compared. To correct for between-group differences in cumulative freezing time, an index calculated as peak biomarker release divided by cumulative freezing time was calculated. Sixty-six CB PVI procedures (G1: 33 patients, G2: 33 patients) were analysed. Pulmonary vein isolation was achieved in all the patients using the simplified SBCB technique only. Mean freezing time (51 ± 10 vs. 33 ± 6 min, P < 0.01) was significantly shorter in G2. All biomarker levels tended to be higher in G2 vs. G1. The indexed biomarkers values were significantly higher in G2: TnT: 18.8 ± 8.5 vs. 32.3 ± 13.6 pg/L/min ( P < 0.01); creatinephosphokinase: 6.7 ± 2.7 vs. 11.7 ± 3.9 U/L/min ( P < 0.01); LDH: 5.2 ± 1.0 vs. 9.1 ± 2.7 U/L/min ( P < 0.01). On a 6-month follow-up (180 days), G2 revealed a significantly higher success rate (20/33 vs. 28/33; P = 0.027). Conclusion Pulmonary vein isolation using the G2 CB increased the myocardial biomarker release index and is linked to a significantly improved 6 months success rate.

Background Currently, 2 different left atrial appendage (LAA) closure systems are available for stroke prevention in nonvalvular atrial fibrillation but comparative data are lacking. Objectives To prospectively compare procedural data and patient outcome for 2 contemporary LAA closure systems and to investigate an alternative antithrombotic treatment regimen in high-risk patients. Methods Patients with nonvalvular atrial fibrillation, with high risk for stroke, and who either had contraindication or were not willing to accept oral anticoagulation were prospectively enrolled. Watchman (Boston Scientific, Natick, MA; group A) or Amplatzer Cardiac Plug (St Jude Medical, Minneapolis, MN; group B) devices were implanted. All patients received antithrombotic therapy for 6 weeks. After repeat transesophageal echocardiography, patients were switched to aspirin. Results Eighty patients were enrolled. There was no statistical difference in patient characteristics in groups A and B: CHA 2 DS 2 VASC score: 4.1 ± 1.5 versus 4.5 ± 1.8; HASBLED score: 3.1 ± 1.1 versus 3.1 ± 1.1, respectively. LAA closure was achieved in 78 of 80 patients (98%) (group A: 38 of 40 [95%] vs group B: 40 of 40 [100%]). There was no difference in procedure time (group A: 48 ± 16 minutes vs group B: 47 ± 15 minutes; P = .69) and fluoroscopy time (group A: 6.0 ± 4.7 minutes vs group B: 7.3 ± 4.4 minutes; P = .25). Major complications included 1 air embolism and delayed tamponade in each group. After 6 weeks, 1 device dislodgment and 4 device-related thrombi were detected. Ninety-four percent of the patients (73 of 77) were switched to aspirin after 6 weeks. During a median follow-up of 364 days (Q1–Q3: 283–539 days), no systemic embolism occurred, but 3 patients died (heart failure: n=2; bleeding: n=1). Conclusions Implantation of both LAA closure devices can be performed with high success rates in high-risk patients. Postprocedural 6 weeks antithrombotic therapy followed by aspirin therapy needs to be confirmed in a larger study.

Background The novel second-generation cryoballoon (CB) facilitates pulmonary vein isolation (PVI) by improved surface cooling. The impact of this redesign on collateral damage is unknown. Objective To investigate the incidence of esophageal lesions after PVI using the second-generation CB and the role of luminal esophageal temperature (LET) measurement as a predictor of lesion formation. Methods Thirty-two consecutive patients underwent PVI using the second-generation 28 mm CB. Target application time was 2×240 seconds. Ninety-two percent of the PVs were isolated after 1 cryoenergy application. Complete PVI was achieved in all patients. LET with 3 thermocouples was continuously measured during cryoenergy application. Freezing was interrupted only if weakening/loss of phrenic nerve function or low LET ( Results The lowest measured LET was−12°C (despite cryoapplication interruption). Postprocedural gastroesophagoscopy was performed after 1–3 days in all patients and showed lesions in 6 of 32 (19%) patients. A minimum LET of≤12°C predicted esophageal lesions with 100% sensitivity and 92% specificity (area under the receiver-operator characteristic curve 0.97; 95% CI 0.93–1.02; P = .001). Persistent phrenic nerve palsy occurred in 2 (6%) patients during ablation at the right inferior pulmonary vein. Repeat gastroesophagoscopy confirmed healing of lesions after 16±14 days. Conclusions Second-generation 28 mm CB PVI is associated with significant esophageal cooling, resulting in lesion formation in 19% of the patients. LET measurement accurately predicts lesion formation and may enhance the safety of the novel device.

Asymptomatic Cerebral Lesions in AF Ablation Background Asymptomatic cerebral lesions (ACL) may occur during atrial fibrillation (AF) ablation. We sought to compare the ACL incidence between 3 contemporary technologies: (1) irrigated radiofrequency current (RFC), (2) the single big cryoballoon (CB), and (3) the endoscopic laser-balloon (LB) in a prospective randomized pilot study. Methods and Results Ninety-nine patients were treated in 3 groups. Diffusion weighted MRI was acquired pre- (n = 20) and 24–48 h postablation (n = 99). After ablation, new ACL were detected in 22% of patients without significant differences between groups (RFC 8/33; CB 6/33; LB 8/33; P = 0.8). The presence of hypertension was identified as the only independent predictor of ACL by univariate regression analysis. During LB ablation, more ablation lesions (140 ± 19 vs 119 ± 18; P = 0.007) were applied during longer procedures (166 ± 36 vs 143 ± 32 min; P = 0.05) in patients with ACL. Univariate analysis revealed that a higher number of ablation lesions predicted ACL (P = 0.02). Conclusion In this prospective, randomized, single-center pilot study, ablation technology did not influence the occurrence of ACL during AF ablation.

Clinical research in cardiology 106(8), 582-589(2017). doi:10.1007/s00392-017-1090-5, Published by Springer, Berlin

Efficacy of the Novel Cryoballoon Introduction The cryoballoon technology has the potential to isolate a pulmonary vein (PV) with a single energy application. However, using the first-generation cryoballoon (CB-1G) repeated freezing or additional focal ablation is often necessary. The novel second-generation cryoballoon (CB-2G) features a widened zone of optimal cooling comprising the whole frontal hemisphere. The aim of this study was to investigate the impact of the novel design on procedural efficacy of cryoballoon PV isolation (CB-PVI). Methods and Results Single transseptal CB-PVI using an endoluminal spiral mapping catheter was performed in 60 consecutive patients (CB-1G, 28 mm, 300 seconds application time: 30 patients; CB-2G, 28 mm, 240 seconds application time: 30 patients). When compared to the CB-1G, using the CB-2G increased single-shot PVI rate from 51% to 84% (P < 0.001) and decreased procedure duration (128 ± 27 vs 98 ± 30 minutes; P < 0.001), and fluoroscopy exposure time (19.5 ± 7.4 vs 13.4 ± 5.3 min; P = 0.001). Effective CB-2G PVI could be performed with increased real-time PVI visualization rate (49% vs 76%; P < 0.001). Time to PVI (TPVI) was shorter in the CB-2G group (79 ± 60 vs. 52 ± 36 seconds; P = 0.049). Procedure-related complications occurred in 2 patients in the CB-1G group and 1 patient in the CB-2G group. Conclusions The CB-2G significantly improved procedural efficacy compared to the CB-1G and provided reliable TPVI measurement. TPVI may be used to adjust application time and number individually in future studies. Final conclusions regarding the safety profile of the CB-2G requires additional research.

In a 66-year-old male (CHA2DS2-VASc score=3) referred for catheter ablation of persistent atrial fibrillation, transesophageal echocardiography revealed a large left atrial appendage (LAA) thrombus (Figure A; Movie I in the Data Supplement), despite continuous treatment with rivaroxaban 20 mg daily. Figure. A , Two-dimensional transesophageal echocardiography (TEE) image showing thrombus inside left atrial appendage (LAA; diameter 9×19 mm). B , LAA landing zone in 2-dimensional TEE. …

Aims Complete pulmonary vein isolation (CPVI) can be achieved by continuous circular lesions (CCL) around the ipsilateral pulmonary veins (PVs) guided by a 3D-mapping system. We investigated whether CPVI can be achieved with a single CCL around the isplilateral PVs without recording PV activity during ablation. Methods and results Fifty patients with atrial fibrillation underwent ablation of CCLs around ipsilateral PVs guided by 3D mapping. One or two Lasso catheters were placed within the PVs. Lasso tracings were hidden to physicians during ablation. After completion of CCLs, Lasso tracings were evaluated. If PV activation was present, conduction gaps (CGs) were identified and ablated with guidance by the local electrogram and the Lasso catheter(s). In 21 patients (42%), CPVI was achieved after ablation of a single CCL around ipsilateral PVs. Pulmonary vein isolation was achieved in 43 patients (86%) in the right-sided PVs and in 21 patients (42%) in the left-sided PVs. In the remaining patients, there were eight CGs in right-sided CCLs and 40 CGs in left-sided CCLs. Conduction gaps along the left CCLs were found at the ridge between the PV ostia and the left atrial appendage in 27 out of 40 CGs (68%). Mean time from the P-wave onset to the earliest PV potential was 112 ± 35 ms in the presence of a CG at the roof, and 166 ± 59 ms in patients with CGs at other locations in left-sided CCLs ( P < 0.05). Conclusion Complete pulmonary vein isolation is difficult to achieve with a single CCL around ipsilateral PVs without continuous recording of PV activation during ablation.

Catheter ablation has become the curative treatment modality for various arrhythmias. Extending the indications for catheter ablation from simple supraventricular tachycardias to complex arrhythmias such as ventricular tachycardia or atrial fibrillation, the investigator faces prolonged procedure times, fluoroscopy exposure and the need for stable and reproducible catheter movement. Recently, remote-controlled robotic catheter ablation has emerged as a novel ablation concept to meet these requirements. This review describes the two available robotic ablation systems and summarizes their clinical applications and current human experience.

Aims Cryothermal energy (CTE) ablation via a balloon catheter (Arctic Front, Cryocath™) represents a novel technology for pulmonary vein isolation (PVI). However, balloon-based PVI approaches are associated with phrenic nerve palsy (PNP). We investigated whether ‘single big cryoballoon’-deployed CTE lesions can (i) achieve acute electrical PVI without left atrium (LA) imaging and (ii) avoid PNP in patients with paroxysmal atrial fibrillation (PAF). Methods and results After double transseptal punctures, one Lasso catheter and a big 28 mm cryoballoon catheter using a steerable sheath were inserted into the LA. PV angiography and ostial Lasso recordings from all PVs were obtained. Selective PV angiography was used to evaluate balloon to LA–PV junction contact. CTE ablation lasted 300 s, and the PN was paced during freezing at right-sided PVs. Twenty-seven patients (19 males, mean age: 56 ± 9 years, LA size: 42 ± 5 mm) with PAF (mean duration: 6.6 ± 5.7 years) were included. PVI was achieved in 97/99 PVs (98%). Median ( Q 1; Q 3) procedural, balloon, and fluoroscopy times were 220 min (190; 245), 130 min (90; 170), and 50 min (42; 69), respectively. Three transient PNP occurred after distal PV ablations. No PV stenosis occurred. Total median ( Q 1; Q 3) follow-up time was 271 days (147; 356), and 19 of 27 patients (70%) remained in sinus rhythm (3-month blanking period). Conclusion Using the single big cryoballoon technique, almost all PVs (98%) could be electrically isolated without LA imaging and may reduce the incidence of PNP as long as distal ablation inside the septal PVs is avoided.

Aims The primary safety and efficacy endpoints of the randomized FIRE AND ICE trial have recently demonstrated non-inferiority of cryoballoon vs. radiofrequency current (RFC) catheter ablation in patients with drug-refractory symptomatic paroxysmal atrial fibrillation (AF). The aim of the current study was to assess outcome parameters that are important for the daily clinical management of patients using key secondary analyses. Specifically, reinterventions, rehospitalizations, and quality-of-life were examined in this randomized trial of cryoballoon vs. RFC catheter ablation. Methods and results Patients (374 subjects in the cryoballoon group and 376 subjects in the RFC group) were evaluated in the modified intention-to-treat cohort. After the index ablation, log-rank testing over 1000 days of follow-up demonstrated that there were statistically significant differences in favour of cryoballoon ablation with respect to repeat ablations (11.8% cryoballoon vs. 17.6% RFC; P = 0.03), direct-current cardioversions (3.2% cryoballoon vs. 6.4% RFC; P = 0.04), all-cause rehospitalizations (32.6% cryoballoon vs. 41.5% RFC; P = 0.01), and cardiovascular rehospitalizations (23.8% cryoballoon vs. 35.9% RFC; P < 0.01). There were no statistical differences between groups in the quality-of-life surveys (both mental and physical) as measured by the Short Form-12 health survey and the EuroQol five-dimension questionnaire. There was an improvement in both mental and physical quality-of-life in all patients that began at 6 months after the index ablation and was maintained throughout the 30 months of follow-up. Conclusion Patients treated with cryoballoon as opposed to RFC ablation had significantly fewer repeat ablations, direct-current cardioversions, all-cause rehospitalizations, and cardiovascular rehospitalizations during follow-up. Both patient groups improved in quality-of-life scores after AF ablation. Clinical trial registration ClinicalTrials.gov identifier: [NCT01490814][1]. [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT01490814&atom=%2Fehj%2Fearly%2F2016%2F07%2F04%2Feurheartj.ehw285.atom

Aims Patients undergoing heart surgery and with history of atrial fibrillation are often treated with intraoperative left atrial appendage (LAA) ligation. Incomplete LAA ligation is often described and can be associated with thrombo-embolic complications. To describe a case series of percutaneous LAA occlusion in patients previously treated with surgical LAA ligation. Methods and results Over 179 patients treated with implantation of an LAA–occluder system at our centre, 3 (1.6%) were previously treated with a surgical LAA suture exclusion (2 males, age 74 ± 3 years). Patients 1 and 3 presented a ‘hammerhead’ LAA morphology with an open neck and were successfully treated with an AGA Cardiac Plug (ACP—St Jude Medical) Device. Patient 2 had a conic monolobar LAA with a small neck, and the occlusion could be performed using a Watchman (Boston Scientific) device. After discharge on dual antiplatelet therapy, all the patients could be switched to single aspirin (ASA) therapy after a 6-week transoesophageal echocardiography control. Conclusion Left atrial appendage occlusion in patient with incomplete surgical ligation using percutaneous LAA occluder devices appears to be feasible, and studies including a larger number of patients are needed.

A 73-year-old paroxysmal atrial fibrillation (AF) male patient (CHADSVASC, 3; HASBLED, 3) was referred to our center for staged AF ablation and left atrial appendage (LAA) closure. Previously, the patient had experienced gastric bleeding on Apixaban. Therefore, we agreed with the patient on additional LAA isolation during AF ablation if electric triggers from the LAA were present. After a single transseptal puncture, selective pulmonary veins (PVs) and LAA angiographies were performed. The 28 mm second generation cyroballoon (CB2; Arctic Front Advance, Medtronic, USA) was advanced into the left atrium. The inner lumen circumferential multipolar catheter (Achieve 20 mm, Medtronic, USA) demonstrated automatic activity in the LAA. Therefore, the CB2 was inflated and positioned at the LAA ostium aiming for …

Xuping Li, MD, Erik Wissner, MD, FHRS, Masashi Kamioka, MD, Hisaki Makimoto, MD, Peter Rausch, MD, Andreas Metzner, MD, Shibu Mathew, MD, Andreas Rillig, MD, Roland Richard Tilz, MD, Alexander Furnkranz, MD, Qi Chen, MD, Qingyong Zhang, MD, Qiming Liu, MD, Shenghua Zhou, MD, Karl-Heinz Kuck, MD, PhD, FHRS, Feifan Ouyang, MD From the Xiangya 2nd Hospital, Central South University, Changsha, Hunan, People’s Republic of China, and Asklepios Klinik St. Georg, Hamburg, Germany.

Six weeks after left atrium appendage occlusion with a 30-mm AGA Cardiac Plug (ACP), an asymptomatic 73-year-old woman presented for routine follow-up. At the time of implant, as shown in Figure A and B, the device position satisfied the 5 signs for correct implantation: tireshaped lobe, disc/lobe separation, disc concavity, two thirds of the lobe distal to the circumflex coronary artery, and device aligned with the left atrium appendage longitudinal axis. Follow-up 2-dimensional transesophageal echocardiography revealed dislocation of the ACP device, dancing in the left atrium (Figure C; Movie I in the online-only Data Supplement). To avoid open-heart surgery, a 24-Fr steerable sheath usually used for mitral valve clipping procedures was introduced into the left atrium after transseptal puncture. Under fluoroscopy and transesophageal echocardiography guidance, the ACP device was snared by wrapping a 30-mm snare around its waist and stabilized by pulling it against the septum (Figure D and E, white arrow). Then, the distal screw of the ACP device was grabbed with a second snare (Figure E and F, black arrow) and successfully retracted into the sheath (Figure G and H; Movie II in the online-only Data Supplement). Despite a history of bleeding before the left atrium appendage occlusion therapy, the patient refused a second implantation attempt and was switched to rivaroxaban 15 mg daily. Follow-up was uneventful. The 30-mm ACP device is equipped with the same number of barbs as smaller devices despite a much larger circumfer ence being a potential reason for a higher risk of dislodgement. This will probably be solved by the new generation ACP occluder (Amulet) with an increased number of barbs.

Stroke is the most devastating complication of atrial fibrillation (AF), and the latter increases the risk of stroke by almost fivefold. AF elimination by catheter ablation should lower the risk of thromboembolic complications. Several studies support this hypothesis, demonstrating rates of stroke in AF patients similar to non-AF populations after successful catheter ablation. Widespread discontinuation of oral anticoagulation after catheter ablation is currently not supported by scientific data but it may be a viable option for patients with a CHA2DS2VASc score of less than 2 and a well-documented stable sinus rhythm.

Aim A novel third-generation cryoballoon (CB3) to perform pulmonary vein isolation (PVI) has recently been released, featuring a shortened distal balloon tip when compared with the second-generation (CB2), possibly allowing for enhanced intra-ablation pulmonary vein (PV) signal mapping. We aimed to investigate procedural efficacy and safety of the CB3 as compared to the CB2. Methods and results We studied 472 consecutive patients who underwent CB-PVI for paroxysmal or persistent atrial fibrillation (CB3: 49 patients; CB2: 423 patients). Detailed procedural data and in-hospital complications were registered in a prospective database. Complete PVI using the CB only was achieved in 98% of patients in each group. Single-freeze PVI was observed in 84/88% (CB2/CB3, P = n.s.) of the PVs. Time-to-PVI (TPVI) was 49 ± 32 (CB2) and 45 ± 27 s (CB3) ( P = n.s.). Time-to-PVI determination rate was higher in the CB3 group (89.5 vs. 82.6%, P = 0.016). Signal noise due to ice formation on mapping electrodes occurred after 70 ± 46 s using CB3 and did not interfere with TPVI determination. Exchange of the spiral mapping catheter with a guide wire was more frequently required in the CB3 group (8.2 vs. 0.7% patients, P < 0.001). Balloon dislodgement during hockey stick manoeuvres occurred in 6.1% patients of the CB3 group only ( P = 0.001). Complication rates were not different between the groups. Conclusion The CB3 offers a higher TPVI determination rate, facilitating dosing schemes based on TPVI, with equally high single-freeze efficacy compared with the CB2. The shortened distal tip of the CB3 requires adaptation of standard catheter manoeuvers to avoid balloon dislodgement.

Cryoballoon ablation has been demonstrated to allow safe and effective isolation of pulmonary veins (PV) for the treatment of paroxysmal atrial fibrillation. Recently, the second-generation cryoballoon device has been developed (Arctic Front Advance, Medtronic CryoCath LP) with improved cooling capabilities by increasing the number of refrigerant injectors, resulting in homogeneous cooling of the balloon surface. In contrast, the first-generation balloon is characterized by a cooling zone concentrated on the equator of the balloon with less cooling around the frontal nose. This limitation is hypothesized to result in incomplete lesion formation in the myocardium contacting this area, specifically the inferior circumference of the inferior PVs.1 The nonhomogeneous cooling of the first-generation device may also explain a relative long time to left atrium-PV block recorded …

Two versus One Repeat Freeze–Thaw Cycle(s). Background: Repeated freezing (bonus applications) during cryoballoon pulmonary vein isolation (PVI) has been suggested to improve lesion durability. However, the long-term clinical effects of repeated freezing have not been investigated. Methods and Results: A total of 51 patients (pts) with paroxysmal atrial fibrillation (AF) underwent PVI using the single big (28 mm) cryoballoon technique. One (27 pts, group I) or 2 bonus applications (24 pts, group II) were performed at all PVs subsequent to PVI. Clinical follow-up consisted of continuous rhythm monitoring by an implantable cardiac monitor (ICM, 24 pts) and serial 7-day Holter-ECG recording (7DH, 27 pts). The primary endpoint was defined as recurrent AF or atrial tachycardia. Acute PVI of all PVs was obtained in 50/51 pts (98%). The median (Q1;Q3) follow-up duration in this study was 384 (213;638) days. The primary endpoint occurred in 48% (group I, 15 pts ICM, 12 pts 7DH) and 46% (group II, 9 pts ICM, 15 pts 7DH), P = 0.84. Procedure- and fluoroscopy-time for group I versus group II was 193 ± 56 minutes versus 207 ± 27 and 33 ± 13 minutes versus 34 ± 11 minutes, respectively. Right phrenic nerve palsy (PNP) occurred in 3 pts (all group II, time to resolution: 128 ± 112 days). In 2 of these pts, PNP occurred during the second bonus application. Conclusion: Application of 2 when compared to 1 freeze–thaw cycle(s) following cryoballoon PVI did not result in improved clinical success but was associated with a higher complication rate. (J Cardiovasc Electrophysiol, Vol. 23, pp. 814-819, August 2012)

Background The optimal energy setting for endoscopic pulmonary vein (PV) isolation (PVI) has not yet been determined. Objective To assess the influence of varying energy settings on the efficacy and safety of endoscopic PVI. Methods In the current prospective study, 30 patients with paroxysmal atrial fibrillation were consented for PVI using the endoscopic ablation system. Ablation was performed by using 5.5 and 7.0 W (group A), 7.0 and 8.5 W (group B), and 8.5 and 10.0 W (group C) along the posterior and anterior portion of each PV, respectively. Intraluminal esophageal temperature was measured via a temperature probe with a cutoff of 38.5°C. Endoscopy was performed 2 days postablation. Results After the completion of the initial circular lesion set, acute PVI was achieved in 25 of the 36 (69%) PVs in group A, in 29 of the 40 (73%) PVs in group B, and in 36 of the 40 (90%) PVs in group C, respectively. The rate of acute PVI was significantly higher in group C than in group A ( P = .025) and group B ( P = .045); there was no difference when comparing group A and group B ( P = .77). Esophageal thermal lesions were detected in 0 of the 10 patients in group A, in 1 of the 10 (10%) patients in group B, and in 1 of the 10 (10%) patients in group C. Mean procedure and fluoroscopy times were 219 ±42 and 30 ± 10, 239 ± 61 and 38 ± 14, and 207 ± 31 and 28 ± 8 minutes for group A, B, and C, respectively. Conclusions The use of higher energy settings increases the efficacy of acute endoscopic ablation system–based PVI without comprising safety. Further investigation is mandatory before final conclusions can be drawn.

This editorial refers to ‘Pulmonary vein ostium shape and orientation as possible predictors of occlusion in patients with drug-refractory paroxysmal atrial fibrillation undergoing cryoballoon ablation’ by A. Sorgente et al. , on page 205. Cryoballoon pulmonary vein isolation (CB-PVI) is attractive for many electrophysiologists because the device allows in principle to isolate the pulmonary veins (PVs) with a single application and a short learning curve.1,2 In order to achieve an effective lesion, the cryoballoon must be positioned with good circumferential tissue contact at the PV ostium, usually ascertained by the absence of contrast media run-off from the balloon tip into the left atrium during PV angiography.1–3 This means that the operator has to face a wide variety of left atrial and PV anatomies with a pre-shaped device that cannot be adapted to a patient's individual anatomy. Device selection is further limited in that the use of the smaller of the two available cryoballoon dimensions (23 and 28 mm) may impose an increased risk of right phrenic nerve …

Cryoballoon pulmonary vein isolation (PVI) currently requires a long cryoballoon application (CBA) time of 240 to 300 seconds, thus repeated ineffective CBA prolongs procedure duration. We hypothesized that cryoballoon temperature (CBT) may be used to discriminate between effective and ineffective CBA during freezing.This study sought to evaluate CBT as a predictor of CBA efficiency.Sixty-six patients with atrial fibrillation underwent PVI using the single big (28 mm) cryoballoon technique. CBT was continuously recorded. After each CBA (300 seconds), a Lasso catheter (Biosense Webster, Inc., Diamond Bar, California) was placed into the target pulmonary vein (PV) to determine whether electrical PV disconnection was present. Only the first CBA at each PV was analyzed to avoid cumulative effects.The CBT was lower during CBA at superior compared with inferior PVs. When individual CBAs were grouped according to successful/failed PVI, CBT was lower for those CBAs that resulted in successful PVI at all time points analyzed. To test the performance of CBT to predict failed CBA, receiver-operator curves were constructed. A minimal CBT of ≥ -42°C/ -39°C (superior/inferior PVs) predicted failed PVI with 73%/92% specificity (area under the curve 0.82/0.81); positive predictive value (PPV) 74%/74%. A minimal CBT of-51°C was invariably associated with PVI. After 120 seconds of freezing, a CBT of ≥ -36°C/ -33°C (superior/inferior PVs) predicted failed PVI with 97%/95% specificity (area under the curve 0.82/0.76); PPV 82%/80%.Balloon temperature predicts successful target PVI during cryoablation and may serve in the early identification of noneffective balloon applications.

Pulmonary vein isolation using a cryoballoon has evolved into a relatively simple alternative for point-by-point radiofrequency ablation because this technology theoretically allows for PV isolation with a single application. Recent clinical studies indicate a high efficacy rate of the procedure; however, the incidence of the most common complication-phrenic nerve palsy (PNP)-has been reported in up to 11.2% of cases. Based on the present data, PNP is mainly associated with the use of the smaller 23 mm balloon. Very recently, it became evident that cryoballoon ablation may be associated with PV stenosis. Thus, the use of cryoballoon technology needs to be combined with a strategy aiming for maximal patient safety. The "single big (28 mm) cryoballoon technique" is a straightforward single-device strategy to deploy cryothermal lesions proximal to the PV ostium at the antrum level, thereby reducing the risk of collateral damage. Using this technique the endpoint of complete PV isolation was achieved in 97% of patients in our laboratory. PNP was observed in 4.4% of patients and resolved within 12 months in the majority of cases. In the future, development of an even bigger (32 mm) cryoballoon may further increase procedural safety by reducing the risk of PNP or PV stenosis.